Neonatal jaundice is caused by excessive bilirubin production and low ability of the newborn liver to metabolize bilirubin, which is a normal developmental process and often does not require special treatment, and early initiation of milk and promotion of bowel movements are beneficial in promoting bilirubin metabolism. However, some severe jaundice can cause bilirubin encephalopathy, which can bring about neurological and audiovisual damage, and some jaundice may indicate hepatobiliary system disease. Therefore, it is very important to correctly understand physiological jaundice and pathological jaundice so that early diagnosis and treatment can be made to avoid serious sequelae. So, how should I observe my baby after the appearance of jaundice? Jaundice usually appears 2 to 3 days after birth and is first manifested as yellowing of the facial skin, which is most pronounced at 4 to 6 days and usually subsides within 7 to 10 days. Premature babies can be delayed until the third week after birth, this is physiological jaundice, is normal. Mothers should pay attention to observation: if the jaundice appears too early or does not subside for more than 10 days, it cannot be considered physiological and should be examined further at the hospital in time to identify pathological jaundice caused by disease. Neonatal jaundice should be considered pathological if: 1, jaundice appears within twenty-four hours after birth. 2. Jaundice persists after two weeks in term newborns and three to four weeks in preterm infants. 3, jaundice accompanied by poor spirit, drowsiness, refusal of milk, temperature does not rise, vomiting, diarrhea, abdominal distension, weight gain, etc. 4, jaundice subsides and then reappears, and is progressively worse.